Rhynchelmis shamanensis, Martin & Kaygorodova, 1998, Martin & Kaygorodova, 1998

Fend, Steven V. & Brinkhurst, Ralph O., 2010, Contributions towards a review of the genus Rhynchelmis Hoffmeister (Clitellata: Lumbriculidae), Zootaxa 2407, pp. 1-27 : 20

Pseudorhynchelmis shamanensis ( Martin & Kaygorodova, 1998)

( Figs. 9 A–L)

(= Pseudorhynchelmis olchonensis sensu Hrabė, 1982)

Supplementry description. Martin collection: Pharyngeal pad strongly developed ( Fig. 9 A). The first lateral blood vessel is visible as a loop in II, but appears to join dorsal and ventral vessels at mid-segment in III. Commissures in IV–V as in II; those in VI–X also unbranched and convoluted, with forward loops, but apparently stay in one segment. No lateral vessels were visible beyond X, but there may be loops into sperm and egg sacs from anterior commissures; dorsal and ventral vessels very thick. Starting about XV, posterior segments with a normal, thick dorsal vessel having cardiac cells, and a supra-intestinal vessel mostly in contact with the perivisceral sinus ( Fig. 9 B).

Spermathecal duct narrow and elongate (length about 5 times width), spermathecal ampulla sac-like, filled with loosely-bundled, unordered sperm. Major, ental portion of atrium tubular, with thin muscle and granular lining cells to over 30 Μm thick; lumen very narrow, about 5 Μm. Ectal end of the atrial duct widens slightly to about 40 μm, and protrudes slightly as a low papilla ( Fig. 9 I). Duct lining cells oblique and elongate, protruding slightly within the widened opening of the papilla, suggesting that the penis is formed by extruded atrial lining cells; some cells of atrial lining extruded beyond the papilla ( Fig. 9 I).

Sectioned Hrabĕ specimens: Pharyngeal pad and supra-intestinal blood vessel as described above ( Figs. 9 C–E). Small nephridia occur irregularly in posterior segments; postseptal mass not strongly developed, with unmodified duct to ectal pore, and convoluted tubules adjacent to ventral blood vessel. Male pores distinctly inside chaetal line, near 10/11 ( Fig. 9 F). Distinct, conical penes are extensions of terminal lining cells, within a shallow sac formed by an ectal expansion of the duct ( Figs. 9 G–H). Vasa deferentia very wide, to 30–40 Μm at ental end; narrowing to about 15–20 Μm in XI along atria ( Figs. 9 J–K). Atrial histology as described above; irregular prostate bundles sparsely cover atria ( Figs. 9 K–L). Pseudorhynchelmis shamanensis differs from the description of P. olchonensis primarily by the lack of glandular cells associated with the chaetae of X. The absence of these glands in the material used by Hrabĕ (1982) in his redescription of P. olchonensis indicate that these specimens should be attributed to P. shamanensis ( Martin et al. 1998).

Figures

FIGURE 9. P. shamanensis and P. alyonae. (A – B, I) P. shamanensis from Martin collection, (C – H, J – L) from Hrabė collection as olchonensis. (A) anterior end showing pharyngeal pad. (B – C) mid-body, showing dorsal and supraintestinal blood vessels. (D) transverse section of pharynx (E) transverse section of a post-clitellar segment showing dorsal and supra-intestinal blood vessels. (F) transverse section of male pores. (G – H) sections of penes. (I) external view of extruded penis. (J) sagittal section showing wide ental portion and narrow ectal portion of vas deferens. (K) atrium joined by narrow portion of a vas deferens. (L) detail of atrial wall. (M) P. alyonae spermatheca. (A, B, I, M whole mounts, C, H, K, L sagittal sections, D – G, J transverse). Scale bars: A – C, E, F = 200 μm; D, K, M = 100 μm; G – J, L = 50 μm.